“He’s all about spooky stories, taking sticks from the park and turning them into stuff,” explained Duhamel, 44. “We literally have a pile of sticks at our house. We could have a giant bonfire at any moment.”

Adds the actor, “He collects sticks, and to him, they’re something. He doesn’t want to go anywhere without them because they’re either a sword or a magic wand.”

Of Axl – the couple’s only child – Duhamel insists, “He’s all boy, man, he is all boy,” noting that the toddler’s threes have been a little more challenging than the notorious “terrible twos.”

“I saw a T-shirt the other day. It was for kids, and it said, ‘Terrible twos? I’m having a great time,’ ” recalls the star. “And that’s kind of it: They don’t know that they’re terrible. They’re just having a blast.”

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